User's Manual

s
E
Ref. : SCT TMO LOG SPEC
163
Revision : B
Sec. Ref. :
Date : 2003-01-22
E. CONFIDENTIAL All rights of reproduction and disclosure reserved.
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4. ANNEX: GPRS QOS PARAMETERS DEFINITION
This Annex defines and explains how some GPRS variables displayed in screens of the GPRS Info menu
of calculated and refreshed.
4.1 DATA TRANSFER 2
ND
SCREEN (LLC) PARAMETERS
This screen is described in 2.5.3.2.
4.1.1 Retransmitted LLC Frame Rate
The Retransmitted LLC Frame Rate is computed over a period of
1 second
. It is defined as follows:
Direction Definition
UPLINK Retrans. Frame Rate = N
RETRANS
/ N
TOTAL
where:
•
N
RETRANS
= number of frames that are not sent for the 1
st
time
•
N
TOTAL
= total number of transmitted frames
DOWNLINK Retrans. Block Rate = N
LOST
/ N
TOTAL
where:
•
N
LOST
= number of frames detected as lost. A frame or a group of frames is considered
as lost when the OT detects a gap in the frame sequence
•
N
TOTAL
= number of frames that have been supposedly sent. It is estimated based on
the Sequence Number of the latest received frame. As a consequence it does not
include retransmitted frames.
The Retransmitted LLC Frame Rate is filtered according to the following criteria:
•
it is reported only if at least one LLC SAPI is in Acknowledged mode
•
it is reported only if N
TOTAL
has changed over the reporting period.
4.1.2 LLC Data throughput
The LLC Data throughput traces are focused on the capacity that is offered by the LLC layer to upper layer
in the User plane. As a consequence the LLC Data throughputs are defined as follows:
•
only I and UI frames are considered
•
only SAPI 3, 5, 9, and 11 are considered (i.e. User SAPIs)
•
in LLC Acknowlegded mode retransmissions are not take into account
•
LLC header parts are not taken into account
The LLC throughputs are computed over a period of
1 second
and reported according to the following
criteria: